Capsule, a system for preparing a potable beverage from such a capsule and use of such a capsule in a beverage preparation device

ABSTRACT

A capsule containing a substance for the preparation of a potable beverage. The capsule comprises an aluminum capsule body having a side wall and an outwardly extending flange and a sealing member at the outwardly extending flange for providing a fluid sealing contact with an enclosing member of a beverage preparation device. The beverage preparation device comprises an annular element having a free contact end which may be provided with a plurality of radially extending open grooves. The sealing member is integral with the outwardly extending flange and comprises at least one projection projecting from the outwardly extending flange. The projection comprising a projection top and is configured such that its projection top exerts a radial force on the free contact end of the annular element if the capsule is positioned in the enclosing member of the beverage preparation device and the enclosing member is closed by means of a closing member of the beverage preparation device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/813,054, filed Nov. 14, 2017, which in turn is a continuation ofInternational App. No. PCT/NL2016/050350 filed May 13, 2016, whichclaims the benefit of and priority to International App. No.PCT/NL2015/050352 filed May 15, 2015, International App. No.PCT/NL2015/000018 filed May 15, 2015, International App. No.PCT/NL2015/050349 filed May 15, 2015, International App. No.PCT/NL2015/050611 filed Sep. 3, 2015. The entire contents of all ofwhich are incorporated herein by reference.

BACKGROUND

The invention relates to a capsule containing a substance for thepreparation of a potable beverage by extracting and/or dissolving thesubstance by means of supplying a fluid under pressure into the capsule,wherein the capsule comprises an aluminum capsule body having a centralcapsule body axis, the aluminum capsule body being provided with abottom, a side wall and an outwardly extending flange, the capsulefurther comprising an aluminum cover attached to the outwardly extendingflange, the cover hermetically closing the capsule, wherein the capsulefurther comprises a sealing member at the outwardly extending flange forproviding a fluid sealing contact with an enclosing member of a beveragepreparation device if the capsule is positioned in the enclosing memberof the beverage preparation device and the enclosing member is closed bymeans of a closing member of the beverage preparation device, such as anextraction plate of the beverage preparation device, such that theoutwardly extending flange of the capsule and at least a portion of thesealing member of the capsule are sealingly engaged between theenclosing member and the closing member of the beverage preparationdevice, wherein the enclosing member of the beverage preparation devicecomprises an annular element having a central annular element axis and afree contact end, the free contact end of the annular element optionallybeing provided with a plurality of radially extending open grooves.

The invention also relates to a system for preparing a potable beveragefrom a capsule using a fluid supplied under pressure into the capsulecomprising:

a beverage preparation device comprising an enclosing member forreceiving the capsule, wherein the enclosing member comprises fluidinjection means for supplying fluid under pressure into the capsule,wherein the beverage preparation device further comprises a closingmember, such as an extraction plate, for closing the enclosing member ofthe beverage preparation device, wherein the enclosing member of thebeverage preparation device further comprises an annular element havinga central annular element axis and a free contact end, the free contactend of the annular element optionally being provided with a plurality ofradially extending open grooves;a capsule containing a substance for the preparation of a potablebeverage by extracting and/or dissolving the substance by means of thefluid supplied under pressure into the capsule by the fluid injectionmeans of the beverage preparation device, wherein the capsule comprisesan aluminum capsule body having a central capsule body axis, thealuminum capsule body being provided with a bottom, a side wall and anoutwardly extending flange, the capsule further comprising an aluminumcover attached to the outwardly extending flange, the cover hermeticallyclosing the capsule, wherein the capsule further comprises a sealingmember at the outwardly extending flange for providing a fluid sealingcontact with the enclosing member of the beverage preparation device ifthe capsule is positioned in the enclosing member of the beveragepreparation device and the enclosing member is closed by means of theclosing member of the beverage preparation device, such that theoutwardly extending flange of the capsule and at least a portion of thesealing member of the capsule are sealingly engaged between theenclosing member and the closing member of the beverage preparationdevice.

Furthermore the invention relates to the use of a capsule in a beveragepreparation device comprising an enclosing member for receiving thecapsule, wherein the enclosing member comprises fluid injection meansfor supplying fluid under pressure into the capsule, wherein thebeverage preparation device further comprises a closing member, such asan extraction plate, for closing the enclosing member of the beveragepreparation device, wherein the enclosing member of the beveragepreparation device further comprises an annular element having a centralannular element axis and a free contact end, the free contact end of theannular element optionally being provided with a plurality of radiallyextending open grooves; wherein the capsule contains a substance for thepreparation of a potable beverage by extracting and/or dissolving thesubstance by means of the fluid supplied under pressure into the capsuleby the fluid injection means of the beverage preparation device, whereinthe capsule comprises an aluminum capsule body having a central capsulebody axis, the aluminum capsule body being provided with a bottom, aside wall and an outwardly extending flange, the capsule furthercomprising an aluminum cover attached to the outwardly extending flange,the cover hermetically closing the capsule, wherein the capsule furthercomprises a sealing member at the outwardly extending flange forproviding a fluid sealing contact with the enclosing member of thebeverage preparation device if the capsule is positioned in theenclosing member of the beverage preparation device and the enclosingmember is closed by means of the closing member of the beveragepreparation device, such that the outwardly extending flange of thecapsule and at least a portion of the sealing member of the capsule aresealingly engaged between the enclosing member and the closing member ofthe beverage preparation device.

Such a capsule, system and use are known from EP-B-1 700 548. In theknown system the capsule is provided with a sealing member having theshape of a step, i.e. a sudden increase of the diameter of the side wallof the capsule, and the enclosing member of this known system has asealing surface acting on the sealing member to provide deflection ofthe sealing member, the sealing surface being inclined so that thedeflection of the sealing member is an inwards and downwards deformationof the step. Furthermore in the known system the enclosing membercomprises a capsule holder and a manually operated or an automaticmechanism for relative displacement of the enclosing member and thecapsule holder. The manually operated or an automatic mechanism appliesa force on the sealing member of the capsule when the enclosing membercloses on the capsule holder. This force should ensure the fluid tightseal between the enclosing member and the capsule. Because the manuallyoperated or an automatic mechanism is arranged to be moved relative tothe base, the sealing capabilities of the system can depend on thepressure of the fluid injected by the fluid injection means. If thepressure of the fluid increases, the force between the sealing member ofthe capsule and the free end of the enclosing member increases too andthereby the force between the sealing member of the capsule and the freeend of the enclosing member increases also. Such a system is describedfurther on. The sealing member of the capsule must be arranged such thatupon reaching the maximum fluid pressure in the enclosing member thesealing member should still provide a fluid sealing contact between theenclosing member and the capsule. However, the sealing member must alsobe arranged such that prior to, or at the start of, brewing when thepressure of the fluid in the enclosing member outside the capsule isrelatively low, the sealing member also provides a fluid sealing contactbetween the enclosing member and the capsule. If at the start ofbrewing, there would not exist a fluid sealing contact between thecapsule and the enclosing member, leakage will occur. However, ifleakage occurs there is a real chance that the pressure in the enclosingmember and outside the capsule will not sufficiently increase forincreasing the force on the sealing member by means of the free end ofthe enclosing member if the manually operated or an automatic mechanismmoves the enclosing member towards the capsule holder. Only if there isa sufficient initial sealing, the pressure in the enclosing member willincrease whereby also the force of the free end of the enclosing memberacting on the sealing member of the capsule will increase for providinga sufficient fluid sealing contact at also the increased fluid pressure.Moreover, this increased fluid pressure outside the capsule alsoprovides an increased fluid pressure inside the capsule which isessential if the capsule is provided with a cover which is arranged totear open on relief members of the capsule holder (also called anextraction plate) of the beverage preparation device under the influenceof fluid pressure in the capsule.

It follows from the above that the sealing member is a member which isvery critical in design. It should be able to provide a fluid sealingcontact between the enclosing member and the capsule at a relatively lowfluid pressure if only a relatively small force is applied on thesealing member by means of the free end of the enclosing member but itshould also provide a fluid sealing contact at a much higher fluidpressure in the enclosing member outside the capsule if a higher forceis applied by means of the free end of the enclosing member to thesealing member of the capsule. In particular when the free contact endof the enclosing member is provided with radially extending open grooveswhich act as air inlet passage once the force between the enclosingmember and the capsule holder is released so that it is easier for auser to take out the capsule, the sealing member must also be able to‘close’ the radially extending open grooves to provide an effectiveseal.

It is an object of the invention to provide an alternative sealingmember which is relatively easy to manufacture, which is environmentallyfriendly if the capsule is disposed of after use and/or which provides asatisfactory sealing both at a relatively low fluid pressure if only arelatively small force is applied on the sealing member by means of thefree end of the enclosing member (sometimes also called initial seal)and at a much higher fluid pressure if a higher force is applied (e.g.during brewing) by means of the free end of the enclosing member to thesealing member of the capsule, even in case of an enclosing member ofwhich the free contact end is provided with radially extending opengrooves.

The invention has also as an object to provide an alternative system forpreparing a potable beverage from a capsule and to provide analternative use of a capsule in a beverage preparation device.

In accordance with the invention there is provided in a first aspect acapsule containing a substance for the preparation of a potable beverageby extracting and/or dissolving the substance by means of supplying afluid under pressure into the capsule, wherein the capsule comprises analuminum capsule body having a central capsule body axis, the aluminumcapsule body being provided with a bottom, a side wall and an outwardlyextending flange, the capsule further comprising an aluminum coverattached to the outwardly extending flange, the cover hermeticallyclosing the capsule, wherein the capsule further comprises a sealingmember at the outwardly extending flange for providing a fluid sealingcontact with an enclosing member of a beverage preparation device if thecapsule is positioned in the enclosing member of the beveragepreparation device and the enclosing member is closed by means of aclosing member of the beverage preparation device, such as an extractionplate of the beverage preparation device, such that the outwardlyextending flange of the capsule and at least a portion of the sealingmember of the capsule are sealingly engaged between the enclosing memberand the closing member of the beverage preparation device, wherein theenclosing member of the beverage preparation device comprises an annularelement having a central annular element axis and a free contact end,the free contact end of the annular element optionally being providedwith a plurality of radially extending open grooves, characterized inthat, the sealing member is integral with the outwardly extending flangeand comprises at least one projection projecting from the outwardlyextending flange, the at least one projection comprising a projectiontop, and wherein the at least one projection is configured such that itsprojection top exerts a radial force on the free contact end of theannular element if the capsule is positioned in the enclosing member ofthe beverage preparation device and the enclosing member is closed bymeans of a closing member of the beverage preparation device. Since thesealing member is integral with the outwardly extending flange andcomprises at least one projection of which the top exerts a radial forceon the free contact end of the annular element if the capsule ispositioned in the enclosing member of the beverage preparation deviceand the enclosing member is closed by means of a closing member of thebeverage preparation device a satisfactory sealing can be obtained. Sucha sealing member is relatively easy to manufacture. Furthermore thecapsule can provide a satisfactory sealing with the free contact endprovided with radially extending open grooves. In addition the sealingfacilitates positioning of the capsule inside the beverage preparationdevice.

In this application the existence of a fluid sealing contact means that0-6%, preferably 0-4%, more preferably 0-2.5% of the total fluidsupplied to the enclosing member for preparing the beverage may leakaway due to leakage between the free contact end and the sealing memberof the capsule.

The invention is in particular advantageous when in an embodiment of acapsule the capsule contains an extractable product as substance for thepreparation of a potable beverage, the extractable product preferablybeing 5-20 grams, preferably 5-10 grams, more preferably 5-7 grams of anextractable product, such as roasted and ground coffee.

In an embodiment of a capsule according to the invention which is inparticular easy to manufacture the outer diameter of the outwardlyextending flange of the capsule is larger than the diameter of thebottom of the capsule. Preferably, the outer diameter of the outwardlyextending flange is approximately 37.1 mm and the diameter of the bottomof the capsule is about 23.3 mm.

The invention is in particular advantageous when in an embodiment of acapsule the thickness of the aluminum capsule body is such that it isdeformed easily if the capsule is positioned in the enclosing member ofthe beverage preparation device and the enclosing member is closed bymeans of a closing member of the beverage preparation device, preferablythe thickness of the aluminum capsule body is 20 to 200 micrometer,preferably 100 micrometer.

The invention is in particular advantageous when in an embodiment of acapsule the thickness of the aluminum cover is 15 to 65 micrometer,preferably 30-45 micrometer and more preferably 39 micrometer.

In an embodiment of a capsule according to the invention the wallthickness of the aluminum cover is smaller than the wall thickness ofthe aluminum capsule body.

In a further embodiment of a capsule according to the invention thealuminum cover is arranged to tear open on a closing member of thebeverage preparation device, such as an extraction plate of the beveragepreparation device under the influence of fluid pressure in the capsule.

In an embodiment of a capsule according to the invention which is inparticular easy to manufacture the side wall of the aluminum capsulebody has a free end opposite the bottom, the outwardly extending flangeextending from the free end of the side wall in a direction at leastsubstantially transverse to the central capsule body axis. Preferably,the outwardly extending flange comprises a curled outer edge, which isbeneficial in obtaining for a satisfactory sealing with the free contactend provided with radially extending open grooves. The radius about thecentral capsule body axis of an inner edge of the curled outer edge ofthe outwardly extending flange is preferably at least 32 mm, so thatclearance from the annular end surface of the enclosure member isensured. It is then preferred that the sealing member is positionedbetween the free end of the side wall of the aluminum capsule body andan inner edge of the curled outer edge of the outwardly extending flangeto obtain a still further satisfactory sealing.

To ensure that the curled outer edge does not interfere with operationof a wide variety of commercially available and future beveragepreparation apparatuses, the curled outer edge of the outwardlyextending flange has a largest dimension of about 1.2 millimeter.

The invention is in particular beneficial for capsules of which theinner diameter of the free end of the side wall of the aluminum capsulebody is about 29.5 mm. The distance between the free end of the sidewall of the aluminum capsule body and an outermost edge of the outwardlyextending flange can be about 3.8 millimeter. The preferred height ofthe aluminum capsule body is about 28.4 mm.

In an embodiment of a capsule according to the invention which after useis easier for a user to take out of a beverage preparation device thealuminum capsule body is truncated, wherein preferably the side wall ofthe aluminum capsule body encloses an angle with a line transverse tothe central capsule body axis of about 97.5°.

In an advantageous embodiment of a capsule according to the inventionthe bottom of the aluminum capsule body has a largest inner diameter ofabout 23.3 mm. It is preferred that the bottom of the aluminum capsulebody is truncated, preferably having a bottom height of about 4.0 mm andthat the bottom further has a generally flat central portion oppositethe cover having a diameter of about 8.3 mm.

In practically all cases a satisfactory seal can be obtained in anembodiment of a capsule according to the invention in which the heightof the sealing member portion to be contacted first by the free end ofthe enclosure member when the enclosure member is closed is at leastabout 0.1 mm, more preferably at least 0.2 mm and most preferably atleast 0.8 mm and at most 3 mm, more preferably at most 2 mm and mostpreferably at most 1.2 mm.

In a preferred embodiment of a capsule according to the invention thecapsule comprises an inner surface, and wherein on the inner surface ofat least the side wall of the capsule an inner coating is provided. Inparticular when the capsule is manufactured by deep drawing the innercoating facilitates the deep drawing process. In case the aluminum coverof the capsule is attached to the outwardly extending flange by means ofa sealing lacquer it is then in particular advantageous when the innercoating being composed of the same material as the sealing lacquer. Independence of the inner coating used it is preferred that the sealingmember is free from an inner coating in order to prevent crumbling offof the inner coating from the sealing member.

In a further embodiment of a capsule according to the invention thecapsule comprises an outer surface, wherein on the outer surface of thecapsule a color lacquer is provided. In order to facilitate in deepdrawing it is preferred to provide on an outer surface of the colorlacquer an outer coating. In dependence of the color lacquer and outercoating used it is preferred that the sealing member is free from acolor lacquer (and consequently the outer coating) in order to preventcrumbling off of the color lacquer/outer coating from the sealingmember.

In a still further embodiment of a capsule according to the inventionthe at least one projection comprises a projection side wall which isinclined with regard to the outwardly extending flange of the aluminumcapsule body, the projection side wall being configured such that it isdeformed easily if the capsule is positioned in the enclosing member ofthe beverage preparation device and the enclosing member is closed bymeans of a closing member of the beverage preparation device. Thisimproves the force exerted on the free contact end and thus improves thesealing. It is then preferred when the distance between the projectionand the side wall of the aluminum capsule body is such that the freecontact end of the annular element is contacted by the projection andthe side wall of the aluminum capsule body if the capsule is positionedin the enclosing member of the beverage preparation device and theenclosing member is closed by means of a closing member of the beveragepreparation device.

In an advantageous embodiment of a capsule according to the inventionthe sealing member in addition to the at least one projection projectingfrom the outwardly extending flange comprises a plateau between theprojection top and the side wall of the aluminum capsule body. It isbeneficial for providing a seal when a bearing is formed by theprojection, plateau and the side wall of the aluminum capsule body,wherein the distance between the projection and the side wall is suchthat the free contact end of the annular element is enclosed by theprojection and the side wall of the aluminum capsule body if the capsuleis positioned in the enclosing member of the beverage preparation deviceand the enclosing member is closed by means of a closing member of thebeverage preparation device.

The projection, the side wall of the aluminum capsule body and theplateau can be arranged such that the free contact end of the annularelement is contacted by the plateau if the capsule is positioned in theenclosing member of the beverage preparation device and the enclosingmember is closed by means of a closing member of the beveragepreparation device.

Alternatively the sealing member can comprises two spaced projections,each projecting from the outwardly extending flange and a plateaubetween the two projections, wherein the distance between the twoprojections is such that the free contact end of the annular element issqueezed between converging surfaces of the two projections if thecapsule is positioned in the enclosing member of the beveragepreparation device and the enclosing member is closed by means of aclosing member of the beverage preparation device. It is then preferredwhen the distance between the two projections is such that the freecontact end of the annular element is contacted by the two projectionsif the capsule is positioned in the enclosing member of the beveragepreparation device and the enclosing member is closed by means of aclosing member of the beverage preparation device. In particular asatisfactory seal can be obtained when the two spaced projections andthe plateau are arranged such that the free contact end of the annularelement is contacted by the plateau if the capsule is positioned in theenclosing member of the beverage preparation device and the enclosingmember is closed by means of a closing member of the beveragepreparation device. The capsule can preferably comprise a bearing forthe enclosing member of the beverage preparation device if the capsuleis positioned in the enclosing member of the beverage preparation deviceand the enclosing member is closed by means of a closing member of thebeverage preparation device, the bearing enclosing at least a portion ofthe free contact end of the annular element and the bearing being formedby the two projections and the plateau there between.

The plateau can be substantially flat or can comprise a curved portion.In particular advantageous is the embodiment of a capsule according tothe invention in which the plateau is V-shaped. In this manner the freecontact end of the annular member is squeezed between the twoprojections providing a satisfactory seal.

A further object of embodiments of the invention is to achieve reliablelow and high pressure sealings against the free contact end of theenclosing member, in particular with little sensitivity to variations indiameter, thickness and shape of the of the free contact end, whichoccur between different models of brewing systems, and non-circularity(e.g. ovality) of the free contact end and/or of the flange of thecapsule. The latter may for instance result from compression of capsulesin a shopping bag or trolley. In an embodiment of the invention, thisobject is achieved by providing that a first one of the two projectionsprojects further from a base portion of the outwardly extending flange,to which base portion the cover is attached, than a second one of thetwo projections.

When the enclosing member closes, if a too large portion of the one ofthe projections projecting furthest from the base portion is locatedunder the axially in line with the free contact end, it is urged awayradially so that the free contact end passes alongside that furthestprojecting one of the projections. This radial displacement alsoentrains the other one of the projections radially towards the freecontact end, so that it is accurately positioned for firm sealingengagement with the free contact end. Moreover, the furthest projectingone of the projections is deformable in radial sense over a relativelylarge distance, so that it can accommodate to relatively largedeviations, while the other one of the projections is relatively stiff,which is advantageous for exerting a firm sealing pressure.

If the first one of the projections is the inner one of the twoprojections, the capsule is particularly suitable for use incommercially available apparatuses such as the Citiz, Lattisima, U,Maestria, Pixie, Inissia and Essenza in which the free contact end ofthe annular element is provided with the plurality of radially extendingopen grooves, the grooves being deeper in the inner surface portion thanin the outer surface portion of the free contact end or the groovesbeing absent in the outer surface portion of the free contact end. Insuch apparatuses, a reliable and accurately positioned seal is obtainedbetween the second one of the projections and the relatively smoothouter surface portion of the free contact end.

For achieving a reliable seal, it is also advantageous if the first oneof the two projections has an extreme top end extending around thecapsule axis at a diameter of 31.9 to 32.4 mm and the second one of thetwo projections has an extreme top end extending around the capsule axisat a diameter of 29.2 to 29.8 mm. Thus, when used in commerciallyavailable coffee making apparatuses such as the Citiz, Lattisima, U,Maestria, Pixie, Inissia and Essenza, an outer edge area of the free endof the enclosing member is firmly pressed against the second projection.

If the plateau is axially spaced from the cover, this area between thefirst and second projections is displaced axially towards the cover asthe enclosing member is closed by means of the closing member of thebeverage preparation device. This causes the first projection and thesecond projection to deform towards the free contact end of the annularelement, due to tilting and “rolling off” of the first projection andthe second projection, thereby increasing the radial contact pressureexerted against the free contact end of the annular element, whichcontributes to achieving a satisfactory seal.

In accordance with the invention there is provided in a second aspect asystem for preparing a potable beverage from a capsule using a fluidsupplied under pressure into the capsule comprising:

a beverage preparation device comprising an enclosing member forreceiving the capsule, wherein the enclosing member comprises fluidinjection means for supplying fluid under pressure into the capsule,wherein the beverage preparation device further comprises a closingmember, such as an extraction plate, for closing the enclosing member ofthe beverage preparation device, wherein the enclosing member of thebeverage preparation device further comprises an annular element havinga central annular element axis and a free contact end, the free contactend of the annular element optionally being provided with a plurality ofradially extending open grooves;a capsule containing a substance for the preparation of a potablebeverage by extracting and/or dissolving the substance by means of thefluid supplied under pressure into the capsule by the fluid injectionmeans of the beverage preparation device, wherein the capsule comprisesan aluminum capsule body having a central capsule body axis, thealuminum capsule body being provided with a bottom, a side wall and anoutwardly extending flange, the capsule further comprising an aluminumcover attached to the outwardly extending flange, the cover hermeticallyclosing the capsule, wherein the capsule further comprises a sealingmember at the outwardly extending flange for providing a fluid sealingcontact with the enclosing member of the beverage preparation device ifthe capsule is positioned in the enclosing member of the beveragepreparation device and the enclosing member is closed by means of theclosing member of the beverage preparation device, such that theoutwardly extending flange of the capsule and at least a portion of thesealing member of the capsule are sealingly engaged between theenclosing member and the closing member of the beverage preparationdevice, characterized in that, the sealing member is integral with theoutwardly extending flange and comprises at least one projectionprojecting from the outwardly extending flange, the at least oneprojection comprising a projection top, and wherein the at least oneprojection is configured such that its projection top exerts a radialforce on the free contact end of the annular element if the capsule ispositioned in the enclosing member of the beverage preparation deviceand the enclosing member is closed by means of a closing member of thebeverage preparation device.

Since the sealing member is integral with the outwardly extending flangeand comprises at least one projection of which the top exerts a radialforce on the free contact end of the annular element if the capsule ispositioned in the enclosing member of the beverage preparation deviceand the enclosing member is closed by means of a closing member of thebeverage preparation device a satisfactory sealing can be obtained. Sucha sealing member is relatively easy to manufacture. Furthermore thecapsule can provide a satisfactory sealing with the free contact endprovided with radially extending open grooves.

The projection or projections may project from at least one base portionof the flange to which base portion the cover is attached. Theprojection or projections may project axially from the base portion in adirection away from the cover. The projection top may constitute aportion of the projection, for instance a half, a third or a quarter ofthe projection, that is axially most distal from the base portion.

Regarding the preferred embodiments of the system as mentioned in thedependent claims which relate to the same features as the features ofthe dependent claims of the capsule reference is made to the above.

The invention is particularly suitable in a system according to theinvention wherein, in use, the maximum fluid pressure in the enclosingmember of the beverage preparation device is in the range of 6-20 bar,preferably between 12 and 18 bar. Even at such high pressures asatisfactory seal between capsule and beverage preparation device can beobtained.

Preferably the system is arranged such that, in use, during brewing, afree end of the enclosing member of the beverage preparation deviceexerts a force F2 on the sealing member of the capsule to provide afluid sealing contact between the outwardly extending flange of thecapsule and the enclosing member of the beverage preparation device,wherein F2 is in the range of 500-1500 N preferably in the range of750-1250 N when the fluid pressure P2 in the enclosing member of thebeverage preparation device outside the capsule is in the range of 6-20bar, preferably between 12 and 18 bar. In particular the system isarranged such that, in use, prior to or at the start of brewing, a freeend of the enclosing member of the beverage preparation device exerts aforce F1 on the sealing member of the capsule to provide a fluid sealingcontact between the outwardly extending flange of the capsule and theenclosing member of the beverage preparation device, wherein F1 is inthe range of 30-150 N preferably in the range of 40-150 N, morepreferably 50-100 N, when the fluid pressure P1 in the enclosing memberof the beverage preparation device outside the capsule is in the rangeof 0.1-4 bar, preferably between 0.1-1 bar.

In an embodiment of a system according to the invention wherein theplurality of radially extending open grooves are uniformly spacedrelative to each other in tangential direction of the free contact endof the annular element of the beverage preparation device so that it iseasier for a user to take out the capsule while a satisfactory sealbetween capsule and beverage preparation device can still be provided.

In an advantageous embodiment of a system according to the invention thelongest tangential width of each groove (top to top, i.e. equal to thegroove to groove pitch) is 0.9-1.1 mm, preferably 0.95 to 1.05 mm, morepreferably 0.98 to 1.02 mm, wherein a maximal height of each groove inan axial direction of the enclosing member of the beverage preparationdevice is 0.01-0.09 mm, preferably 0.03 to 0.07 mm, more preferably0.045 to 0.055 mm, most preferred 0.05 mm and wherein the number ofgrooves is 90 to 110, preferably 96. The radial width of the annular endsurface at the location of the grooves may for instance be 0.05-0.9 mm,preferably 0.2-0.7 mm and more preferably 0.3-0.55 mm. The invention isin particular suitable when applied to an embodiment of a systemaccording to the invention in which during use when the closing memberof the beverage preparation device closes the enclosing member of thebeverage preparation device at least the free contact end of theenclosing member of the beverage preparation device can move relative tothe closing member of the beverage preparation device under the effectof the pressure of the fluid in the enclosing member of the beveragepreparation device towards the closing member of the beveragepreparation device for applying the maximum force between the flange ofthe capsule and the free end of the enclosing member of the beveragepreparation device. The enclosing member may comprise a first part and asecond part wherein the second part comprises the free contact end ofthe enclosing member wherein the second part can move relative to thefirst part between a first and second position. The second part can movefrom the first positon towards the second position in the direction ofthe closing member under the influence of fluid pressure in theenclosing member. The force F1 as discussed above may be reached if thesecond part is in the first position with a fluid pressure P1. The forceF2 as discussed above may be reached if the second part is moved towardsthe second position under the influence of the fluid pressure P2 in theenclosing member.

In accordance with the invention there is provided in a third aspect ause of a capsule according to the invention in a beverage preparationdevice comprising an enclosing member for receiving the capsule, whereinthe enclosing member comprises fluid injection means for supplying fluidunder pressure into the capsule, wherein the beverage preparation devicefurther comprises a closing member, such as an extraction plate, forclosing the enclosing member of the beverage preparation device, whereinthe enclosing member of the beverage preparation device furthercomprises an annular element having a central annular element axis and afree contact end, the free contact end of the annular element optionallybeing provided with a plurality of radial grooves; wherein the capsulecontains a substance for the preparation of a potable beverage byextracting and/or dissolving the substance by means of the fluidsupplied under pressure into the capsule by the fluid injection means ofthe beverage preparation device, wherein the capsule comprises analuminum capsule body having a central capsule body axis, the aluminumcapsule body being provided with a bottom, a side wall and an outwardlyextending flange, the capsule further comprising an aluminum coverattached to the outwardly extending flange, the cover hermeticallyclosing the capsule, wherein the capsule further comprises a sealingmember integral with the outwardly extending flange for providing afluid sealing contact with the enclosing member of the beveragepreparation device if the capsule is positioned in the enclosing memberof the beverage preparation device and the enclosing member is closed bymeans of the closing member of the beverage preparation device, suchthat the outwardly extending flange of the capsule and at least aportion of the sealing member of the capsule are sealingly engagedbetween the enclosing member and the closing member of the beveragepreparation device. Regarding the advantage of the inventive use and thepreferred embodiments of the use as mentioned in the dependent claimswhich relate to the same features as the features of the dependentclaims of the capsule or the dependent claims of the system reference ismade to the above.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be further elucidated by means of, non-limiting,examples referring to the drawing, in which:

FIG. 1 shows a schematic representation of an embodiment of a systemaccording to the invention;

FIG. 2 in a perspective view shows an embodiment of a beveragepreparation device of a system according to the invention showing thefree contact end of the enclosing member of the beverage preparationdevice with the plurality of radially extending open grooves;

FIG. 3A in cross section shows an embodiment of a capsule according tothe invention before use;

FIG. 3B shows an enlarged detail of a the capsule of FIG. 3A showing theoutwardly extending flange and the sealing member;

FIG. 3C shows an enlarged detail of the outwardly extending flange ofthe capsule in FIGS. 3A and 3B after use;

FIG. 4A shows a first embodiment of a sealing member at the outwardlyextending flange of a capsule according to the invention;

FIG. 4B shows a second embodiment of a sealing member at the outwardlyextending flange of a capsule according to the invention;

FIG. 4C shows a third embodiment of a sealing member at the outwardlyextending flange of a capsule according to the invention;

FIG. 4D shows a fourth embodiment of a sealing member at the outwardlyextending flange of a capsule according to the invention;

FIG. 4E shows a fifth embodiment of a sealing member at the outwardlyextending flange of a capsule according to the invention;

FIG. 4F shows a sixth embodiment of a seal member at the outwardlyextending flange of a capsule according to the invention;

FIG. 4G shows a seventh embodiment of a seal member at the outwardlyextending flange of a capsule according to the invention;

FIGS. 5A and 5B are schematic representations of successive stages ofdeformation of the seventh embodiment of a seal member at the outwardlyextending flange of a capsule according to the invention if the capsuleis positioned in the enclosing member of the beverage preparation deviceand as the enclosing member is closed by means of a closing member ofthe beverage preparation device; and

FIG. 6 is a schematical cross-section view of a deformed flange portionand a portion of an enclosing member where a bridge is present betweeninner and outer rims of a free end of the enclosing member.

In the figures and the following description, like reference numeralsrefer to like features.

DETAILED DESCRIPTION

FIG. 1 shows a schematic representation, in cross sectional view, of anembodiment of a system 1 for preparing a potable beverage from a capsuleusing a fluid supplied under pressure into the capsule. The system 1comprises a capsule 2, and a beverage preparation device 4. The device 4comprises enclosing member 6 for holding the capsule 2. The device 4further comprises a closing member, such as an extraction plate, 8 forsupporting the capsule 2.

In FIG. 1 a gap is drawn between the capsule 2, the enclosing member 6and the extraction plate 8 for clarity. It will be appreciated that, inuse, the capsule 2 may lie in contact with the enclosing member 6 andthe extraction plate member 8. Commonly, the enclosing member 6 has ashape complementary to the shape of the capsule 2. The beveragepreparation device 4 further comprises a fluid injection means 10 forsupplying an amount of a fluid, such as water, under a pressure in therange of 6-20 bar, preferably between 12 and 18 bar, to the exchangeablecapsule 2.

In the example shown in FIG. 1, the exchangeable capsule 2 comprises analuminum capsule body 12 having a central capsule body axis 12A and analuminum cover 14. In the present context, the meaning of ‘aluminum’ isunderstood to also include aluminum alloy. In this example, the aluminumcapsule body 12 comprises a side wall 16, a bottom 18 closing the sidewall 16 at a first end, and a outwardly extending flange 20 extendingoutwardly of the circumferential wall 16 at a second end opposite thebottom 18. The side wall 16, the bottom 18 and the cover 14 enclose aninner space 22 comprising a substance for the preparation of a potablebeverage by extracting and/or dissolving the substance. Preferably thesubstance is an extractable product for the preparation of a potablebeverage, the extractable product preferably being 5-20 grams,preferably 5-10 grams, more preferably 5-7 grams of roasted and groundcoffee for the preparation of a single beverage. The capsule isinitially sealed, i.e. is hermetically closed prior to use.

The system 1 of FIG. 1 comprises bottom piercing means 24 for piercingthe bottom 18 of the capsule 2 for creating at least one entranceopening 25 in the bottom 18 for supplying the fluid to the extractableproduct through the entrance opening 25.

The system 1 of FIG. 1 further comprises cover piercing means 26, hereembodied as protrusions of the closing member 8, for piercing the cover14 of the capsule 2. The cover piercing means 26 may be arranged to tearthe cover 14 once a (fluid) pressure inside the inner space 22 exceeds athreshold pressure and presses the cover 14 against the cover piercingmeans 26 with sufficient force. The aluminum cover 14 thus is arrangedto tear open on the closing member 8 of the beverage preparation deviceunder the influence of fluid pressure in the capsule.

The capsule 2 further comprises a sealing member 28 integral with theoutwardly extending flange, in FIGS. 1, 3A and 3B indicated as a generalbox but more detailed described with regard to FIG. 4, which sealingmember 28 is arranged for providing a fluid sealing contact with theenclosing member 6 if the capsule 2 is positioned in the enclosingmember 6 and the enclosing member 6 is closed by means of the extractionplate 8, such that the outwardly extending flange 20 of the capsule 2and at least a portion of the sealing member 28 are sealingly engagedbetween the enclosing member 6 and the extraction plate 8. This meansthat a fluid sealing contact between the sealing member and the freecontact end is established.

As shown in FIG. 2 the enclosing member 6 of the beverage preparationdevice comprises an annular element 41 having a central annular elementaxis 41A and a free contact end 30. The free contact end 30 of theannular element 41 is provided with a plurality of radially extendingopen grooves 40. The plurality of radially extending open grooves 40 areuniformly spaced relative to each other in tangential direction of thefree contact end 30 of the annular element 41. The longest tangentialwidth of each groove 40 is 0.9-1.1 mm, preferably 0.95 to 1.05 mm, morepreferably 0.98 to 1.02 mm, wherein a maximal height of each groove 40in an axial direction of the enclosing member 6 is 0.01-0.09 mm,preferably 0.03 to 0.07 mm, more preferably 0.045 to 0.055 mm, and mostpreferred 0.05 mm. The number of grooves 40 lies in the range of 90 to110, preferably 96. Usually, the radial width of the free end at thelocation of the grooves is 0.05-0.9 mm, more specifically 0.2-0.7 mm,more specifically 0.3-0.55 mm.

An embodiment of a capsule according to the invention is shown moredetailed in FIGS. 3A and 3B. In the shown embodiment the outer diameterODF of the outwardly extending flange 20 is larger than the diameter DBof the bottom 18 of the capsule 2. In the shown embodiment the outerdiameter ODF of the outwardly extending flange 20 is approximately 37.1mm and the diameter DB of the bottom 18 is about 23.3 mm. The thicknessof the aluminum capsule body 12 is such that it is deformed easily ifthe capsule is positioned in the enclosing member of the beveragepreparation device and the enclosing member is closed by means of aclosing member of the beverage preparation device, preferably thethickness of the aluminum capsule body is 100 micrometer, but in otherembodiments the thickness can be 20 to 200 micrometer.

In the shown embodiment, the wall thickness of the aluminum cover 14 is39 micrometer. The wall thickness of the aluminum cover 14 is preferablysmaller than the thickness of the aluminum capsule body 12.

The side wall 16 of the aluminum capsule body 12 has a free end 42opposite the bottom 18. The inner diameter IDF of the free end 42 of theside wall 16 of the aluminum capsule body 12 is about 29.5 mm. Theoutwardly extending flange 20 extends from that free end 42 in adirection at least substantially transverse to the central capsule bodyaxis 12A. The outwardly extending flange 20 comprises a curled outeredge 43 which is beneficial for obtaining a seal between the capsule andthe enclosing member. In the shown embodiment the curled outer edge 43of the outwardly extending flange 20 has a largest dimension of about1.2 millimeter. The distance DIF between the free end 42 of the sidewall 16 of the aluminum capsule body 12 and an inner edge 43A of thecurled outer edge 43 is about 2.7 mm, while the distance DOF between thefree end 42 of the side wall 16 of the aluminum capsule body 12 and anoutermost edge 43B of the outwardly extending flange 20 is about 3.8millimeter. The radius about the central capsule body axis of the inneredge 43A of the curled outer edge 43 is preferably at least 32 mm.

As shown in FIGS. 3A and 3B the sealing member 28 is positioned betweenthe free end of the side wall 16 of the aluminum capsule body 12 and theinner edge 43A of the curled outer edge 42 of the outwardly extendingflange. The sealing member 28 is indicated as a general box, but will bedescribed in more detail below. Irrespective of the embodiment of thesealing member 28 the height of the sealing member portion to becontacted first by the free end of the enclosure member when theenclosure member is closed is at least about 0.1 mm, more preferably atleast 0.2 mm and most preferably at least 0.8 mm and at most 3 mm, morepreferably at most 2 mm and most preferably at most 1.2 mm for providinga correct seal.

As can be seen from FIG. 3A the aluminum capsule body 12 is truncated.In the embodiment shown, the side wall 16 of the aluminum capsule body12 encloses an angle A with a line transverse to the central capsulebody axis 12A of about 97.5°. The bottom 18 of the aluminum capsule body12 has a largest inner diameter DB of about 23.3 mm. The bottom 18 ofthe aluminum capsule body 12 is also truncated, and in the shownembodiment has a bottom height BH of about 4.0 mm. The bottom 18 furtherhas a generally flat central portion 18A opposite the cover 14, whichcentral portion 18A has a diameter DEE of about 8.3 mm and in whichcentral portion 18A the entrance opening(s) 25 may be made. The entranceopenings may also be made in the truncated portion between the centralportion 18A and the side wall 16. The total height TH of the aluminumcapsule body 12 of the capsule is about 28.4 mm.

The system 1 shown in FIG. 1 is operated as follows for preparing a cupof a potable beverage, in the present example coffee, wherein thesubstance is roasted and ground coffee.

The capsule 2 is placed in the enclosing member 6. The extraction plate8 is brought into contact with the capsule 2. The bottom piercing means24 pierce the bottom 18 of the capsule 2 for creating the entranceopenings 25. The fluid, here hot water under pressure, is supplied tothe extractable product in the inner space 22 through the entranceopenings 25. The water will wet the coffee grounds and extract thedesired substances to form the coffee beverage.

During supplying the water under pressure to the inner space 22, thepressure inside the capsule 2 will rise. The rise in pressure will causethe cover 14 to deform and be pressed against the lid piercing means 26of the extraction plate. Once the pressure reaches a certain level, thetear strength of the cover 14 will be surpassed and the cover 14 willrupture against the lid piercing means 26, creating exit openings. Theprepared coffee will drain from the capsule 2 through the exit openingsand outlets 32 (see FIG. 1) of the extraction plate 8, and may besupplied to a container such as a cup (not shown).

The system 1 is arranged such that prior to or at the start of brewing,the free end 30 of the enclosing member 6 exerts a force F1 on thesealing member 28 of the capsule 2 to provide a fluid sealing contactbetween the outwardly extending flange 20 of the capsule 2 and theenclosing member 6 of the beverage preparation device, wherein F1 is inthe range of 30-150 N preferably 40-150 N, more preferably 50-100 N,when the fluid pressure P1 in the enclosing member of the beveragepreparation device outside the capsule is in the range of 0.1-4 bar,preferably 0.1-1 bar. During brewing, the free end 30 of the enclosingmember 6 exerts a force F2 on the sealing member 28 of the capsule 2 toprovide a fluid sealing contact between the outwardly extending flange20 of the capsule 2 and the enclosing member 6, wherein the force F2 isin the range of 500-1500 N, preferably in the range of 750-1250 N, whenthe fluid pressure P2 in the enclosing member 6 of the beveragepreparation device outside the capsule 2 is in the range of 6-20 bar,preferably between 12 and 18 bar. In the shown embodiment the freecontact end of enclosing member 6 can move relative to the extractingplate 8 under the effect of the pressure of the fluid in the enclosingmember 6 device towards the extraction plate 8 for applying the maximumforce F2 between the outwardly extending flange 20 and the free end 30of the enclosing member 6. This movement can take place during use, i.e.in particular at the start of brewing and during brewing. The enclosingmember 6 has a first part 6A and a second part 6B wherein the secondpart comprises the free contact end 30. The second part 6B can moverelative to the first part 6A between a first and second position. Thesecond part 6B can move from the first positon towards the secondposition in the direction of the closing member 8 under the influence offluid pressure in the enclosing member 6. The force F1 as discussedabove may be reached if the second part 6B is in the first position witha fluid pressure P1. The force F2 as discussed above may be reached ifthe second part 6B is moved towards the second position under theinfluence of the fluid pressure P2 in the enclosing member 6.

As a result of the force applied the sealing member 28 of the capsuleaccording to the invention undergoes a plastic deformation and closelyconforms to the grooves 40 of the free contact end 30 and thus providesa fluid sealing contact between the enclosing member 6 and the capsule 3at a relatively low fluid pressure during start up of brewing but alsoprovides a fluid sealing contact at the much higher fluid pressure inthe enclosing member outside the capsule during brewing. This closeconformation to the grooves 40 of the enclosing member is indicated inFIG. 3C which shows the capsule 2 of the invention after use, and whichclearly indicates that the outwardly extending flange 20 comprisesdeformations 40′ which conform to the grooves 40 of the enclosingmember.

Now exemplary embodiments of a sealing member 28 at the outwardlyextending flange 20 of the capsule 2 according to the invention will bedescribed in more detail with regard to FIG. 4.

FIG. 4A shows a first embodiment of a sealing member 28 forming anadditional bearing at the outwardly extending flange 20 of a capsule 2according to the invention. The sealing member and the remainder of thecapsule body are made of the same plate material. The sealing member 28comprises two spaced projections 50 and 51, each projecting axially froma base portion of the outwardly extending flange 20, to which baseportion the cover 14 is attached, in a direction away from the cover 14.A plateau 52 is present between the two projections 50 and 51. Thedistance between the two projections 50 and 51 is such that the freecontact end of the annular element 6 is squeezed between convergingsurfaces of the two projections 50 and 51 if the capsule is positionedin the enclosing member of the beverage preparation device and theenclosing member is closed by means of a closing member of the beveragepreparation device. In the embodiment shown in FIG. 4A the plateau ispositioned at a distance above the portion of the outwardly extendingflange 20 between the sealing member 28 and the curled edge 43 and issubstantially flat. The distance between the two projections 50 and 51is further such that the free contact end of the annular element iscontacted by the two projections 50 and 51 if the capsule is positionedin the enclosing member of the beverage preparation device and theenclosing member is closed by means of a closing member of the beveragepreparation device. Further, the two spaced projections 50, 51 and theplateau 52 are arranged such that the free contact end of the annularelement is contacted by the plateau if the capsule is positioned in theenclosing member of the beverage preparation device and the enclosingmember is closed by means of a closing member of the beveragepreparation device. As can be seen in FIG. 4A each projection 50, 51comprises a projection side wall which is inclined with regard to theoutwardly extending flange 20 of the aluminum capsule body. Theprojection side wall is configured such that it is deformed easily ifthe capsule is positioned in the enclosing member of the beveragepreparation device and the enclosing member is closed by means of aclosing member of the beverage preparation device.

FIG. 4B shows a second embodiment of a sealing member 28 at theoutwardly extending flange 20 of a capsule according to the invention.When compared with FIG. 4A the following differences are noted. Eachprojection 50, 51 now comprises a projection side wall which istransverse with regard to the outwardly extending flange 20 of thealuminum capsule body. Further, in this second embodiment the plateau 52is curved, preferably conforming to the shape of the free contact end ofthe annular element 6.

FIG. 4C shows a third embodiment of a sealing member 28 at the outwardlyextending flange 20 of a capsule according to the invention, whichtogether with the side wall 16 of the aluminum capsule body forms anadditional bearing for the enclosing member. The shown sealing member 28comprises a projection 53 projecting from the outwardly extending flange20 and an inclined, substantially flat plateau 52 between a roundedtopmost end portion of the projection 53 and the side wall 16 of thealuminum capsule body. In this embodiment the bearing is formed by theprojection 53, the plateau 52 and the side wall 16 of the aluminumcapsule body. The distance between the top of the projection 53 and theside wall 16 is such that the free contact end of the annular element 6is enclosed by the projection 53 and the side wall 16 of the aluminumcapsule body if the capsule is positioned in the enclosing member of thebeverage preparation device and the enclosing member is closed by meansof a closing member of the beverage preparation device. In particularthe distance between the projection 53 and the side wall 16 of thealuminum capsule body is such that the free contact end of the annularelement 6 is contacted by the projection 53 and the side wall 16 and inthe shown embodiment also the plateau 52 of the aluminum capsule body ifthe capsule is positioned in the enclosing member of the beveragepreparation device and the enclosing member is closed by means of aclosing member of the beverage preparation device.

FIG. 4D shows a fourth embodiment of a sealing member 28 at theoutwardly extending flange 20 of a capsule according to the invention,which together with the side wall 16 of the aluminum capsule body formsan additional bearing for the enclosing member. When compared with FIG.4C the following differences are noted. In this fourth embodiment theplateau 52 is curved, and comprises a curved portion and also a flatportion which is situated at the same level as the portion of theoutwardly extending flange 20 between the projection 53 and the curvededge 43. The curved portion preferably conforms to the shape of the freecontact end of the annular element 6. FIG. 4E shows a fifth embodimentof a sealing member 28 at the outwardly extending flange 20 of a capsuleaccording to the invention, which together with the side wall 16 of thealuminum capsule body forms a bearing for the enclosing member. Whencompared with FIG. 4D the following difference is noted. In this fifthembodiment the flat portion of the plateau 52 is situated at a distanceabove the portion of the outwardly extending flange 20 between theprojection 53 and the curved edge 43. The distance between 2 theprojection 53 is preferably 0.9-1.25 mm, which allows the free end ofthe closing member of widely used and commercially available beveragepreparation devices (such as the Citiz, Lattisima, U, Maestria, Pixie,Inissia and Essenza) to be reliably squeezed against the projections 53with the side wall 16 in close proximity thereto.

In the embodiments shown in FIGS. 4C to 4E the projection 53 comprisesan outer projection side wall 54 which is transverse to the portion ofthe outwardly extending flange between the projection 53 and the curlededge 43, but in other embodiments this outer projection side wall 54 canbe inclined with regard to the portion of the outwardly extending flange20.

In all the embodiments shown in FIGS. 4A to 4E each of the projectionscomprises a projection top constituting a portion of the projection, forinstance a half, a third or a quarter of the projection, that is axiallymost distal from the base portion of the flange 28 to which the cover 14is attached. At least one projection but preferably all projectionsforming the additional bearing is/are configured such that itsprojection top exerts a radial force on the free contact end of theannular element 6 if the capsule is positioned in the enclosing memberof the beverage preparation device and the enclosing member is closed bymeans of a closing member of the beverage preparation device.

FIG. 4F shows a sixth embodiment of a seal member 28 at the outwardlyextending flange 20 of a capsule according to the invention. Whencompared with e.g. FIG. 4B the following differences are noted. In thissixth embodiment the plateau 52 is V-shaped, with the bottom of theV-shaped being at the same level as the base portion of the outwardlyextending flange 20 between the outer projection 51 and the curled edge43. In this manner no bearing for the free contact end of the annularmember 6 is formed, but the projection top of the inner projection 50exerts a radial force direct outwardly on the free contact end of theannular element 6 and the projection top of the outer projection 51exerts a radial force direct inwardly on the free contact end of theannular element 6 if the capsule is positioned in the enclosing memberof the beverage preparation device and the enclosing member is closed bymeans of a closing member of the beverage preparation device. In thismanner the free contact end is squeezed by the sealing member 28 therebyproviding a satisfactory seal.

In capsules in which the sealing structure 28 has projections 50, 51 anda plateau or through 52 in between, as by way of example shown in FIGS.4A, 4B, and 4F, the center of the plateau or through 52, which extendscircumferentially around the center axis of the capsule, preferably hasa diameter of 29-33 mm, more preferably 30.0-31.4 mm and most preferably30.3-31.0 mm, so that (seen in radial cross-section) the free end of theclosing member of widely used and commercially available beveragepreparation devices (such as the Citiz, Lattisima, U, Maestria, Pixie,Inissia and Essenza) lands accurately centered between the projections50, 51 and the squeezing effect is evenly distributed over the inner andouter projections 50, 51. For effective squeezing in such apparatuses,the distance between projections 50, 51 is preferably 0.9-1.25 mm.

FIG. 4G shows a seventh embodiment of a seal member 28 at the outwardlyextending flange 20 of a capsule according to the invention. As alsoshown in FIG. 2, the enclosing member 6 of the beverage preparationdevice has an annular element 41 having a free contact end 30 with aplurality of radially extending open grooves 40 of which some are shownin FIG. 4G.

As in the examples shown in FIGS. 4A, 4B and 4F, the sealing member 28has two spaced projections 50 and 51, each projecting axially from abase portion 23 of the outwardly extending flange 20, to which baseportions 21, 23 the cover 14 is attached, in a direction away from thecover 14. As in the example shown in FIG. 4F, a plateau 52 having arounded bottom is located between the two projections 50 and 51.

A difference compared with the examples shown in FIGS. 4A, 4B and 4F isthat, in the example shown in FIG. 4G, a first one of the twoprojections 51 projects further from a base portion 23 of the outwardlyextending flange 20 than a second one of the two projections 50.

Another difference is that a bottom 56 of an annular trough 55 betweenthe inner projection 51 and the side wall 16 is axially spaced from thebase portion 23 to which base portion the cover is attached. Preferably,the axial distance from the bottom 56 to the cover is smaller than theaxial distance from the plateau 52 to the cover.

When the enclosing member 6 and/or the closing member 8 is moved towardsthe other with the sealing member 28 of the capsule in between, the freecontact end 30 of the annular element 41 may first contact the first oneof the two projections 51 and subsequently contacts the second one ofthe two projections (FIG. 5A).

If and when the free contact end 30 of the annular element 41 contactsthe inner one of the two projections 51, the capsule is centeredrelative to the enclosing member 6. Moreover, if the inner one of thetwo projections 51 is radially too far to the outside, for instancelocally due to non-circularity or off-centered positioning of thecapsule, or generally due to the free contact area having a relativelysmall diameter, the free contact end urges the inner one of the twoprojections 51 radially inwardly. The outer one of the two projectionsis thereby entrained inwardly, so that a reliable firm sealing pressureis exerted onto the outer one of the two projections 50 in spite of therelatively small deformability of that outer projection 51 due to itssmaller height. The relatively large stiffness of the outer one of thetwo projections 50, allows a large contact force to be exerted as it isdeformed (FIG. 5B), the relatively high counter pressure provides aparticularly reliable seal with high pressure resistance. Also, theouter one of the two projections 50 is then urged outwardly, which loadis counteracted by hoop stress in the outer one of the two projections,which is evenly distributed circumferentially so that an evenlydistributed sealing pressure is achieved.

As can also be seen from FIG. 5a , the free contact end 30 of theannular element 41 has an inner circumferential surface portion 71contacting the inner projection 51 and an outer circumferential surfaceportion 70 contacting the outer projection 50. The radially extendingopen grooves 40 are deeper in the inner surface portion 71 than in theouter surface portion 70 or the grooves may be absent in the outersurface portion 70. Thus, the smaller, relatively stiff outer projection50 is firmly and accurately pressed against the relatively smooth outersurface portion 70 of the free contact end 30.

The distance between the two projections 50 and 51 is such thatultimately (FIGS. 5A and 5B) the free contact end 30 of the annularelement 41 is squeezed between converging surfaces of the twoprojections 50 and 51 when the enclosing member is fully closed by meansof the closing member.

The plateau 52 is axially spaced from the cover 14. As illustrated byFIG. 5B, this allows the plateau 52 between the projections 50, 51 to bedisplaced in the direction of relative movement of the free end 30 ofthe annular element 41 as the enclosing member 6 is closed, urging theprojections 50, 51 to be tilted and roll off inwardly against the freeend 30 of the annular element 41 as the enclosing member 6 is closed.This increases the radial sealing pressure that is exerted (in additionto the axial closing pressure), so that an increased sealing pressure isavailable for providing a satisfactory seal.

More specifically, three stages may be distinguished if the sealingmember of the rim according to FIGS. 4G, 5A, 5B and 6 is clamped betweenthe annular element 41 of the enclosing member 6 and the closing member8.

In the first stage contact between the annular element 41 and thesealing member 28 is established, where necessary under guidance of theinner projection 51 as described above and an initial seal is createdbetween a generally inwardly facing surface portion of the outerprojection 50 and an outer surface portion 70 of the free end 30 of theannular element 41. The radial location of this inwardly facing surfaceportion of the outer projection 50 and the local radius of curvature ofthe outer projection 50 is arranged to ensure that the faces contactingeach other are oriented almost vertically. This allows a very strongwedging effect to be achieved, so that a very small vertical closingforce results in very large horizontal contact pressures. These largehorizontal forces are exerted with little deformation of the outerprojection 50, because the reaction forces generated by the surfacecontact are contained mainly by hoop stress in the outer projection 50.Also, such hoop stresses are largely independent of the remainder of thesealing member 28, so that high stiffness for exerting a large sealingforce can be combined with flexibility to accommodate to tolerances andmisplacement of the capsule.

Because the bottom 56 of the annular trough, and accordingly the innerfoot of the inner projection stands off from the cover friction andstiffness in the lateral directions are reduced and the sealing member28 has a high degree of flexibility to accommodate misalignment andtolerance effects without undue distortion of the sealing faces. Thisalso contributes to maintain the almost vertical orientations of thecontacting faces even if misalignment and tolerances are accommodated toby lateral displacement of the contacting face of the sealing member 28.

In the second stage, the closure and further compression of the brewchamber onto the sealing ring is supported by the build-up of hydraulicpressure. As the compressive force builds, the bottom 56 of the annulartrough 55 is pushed downwards by the mechanical and hydraulic loadingand the whole sealing member pivots about an outer lower end 57 of theouter projection 50 until the bottom 56 of the annular trough 55 touchesthe cover (FIG. 5B). This pivoting movement results in both a ‘rigidbody’ type motion of the sealing member 28 as well as deformation of thesealing member shape, both factors result in addition contact pressurebeing transferred to the primary sealing face. Since much of thedeformation occurs plastically, the contact region conforms effectivelyto sealing area and allows some misalignment and manufacturingtolerances to be accommodated.

In the third stage, a further increase of the axial (here vertical)force causes further deformation of the sealing member 28 (FIG. 5B). Inthe present embodiment a reliably very leak-tight seal at a highpressure drop at high contact pressure is obtained by deformation of asloping section 58 forming a transition from the outer projection 50 tothe plateau, which section 58 constitutes a relatively straight sectionbetween more curved sections of the plateau 52 and the outer projection50. Such deformation results in a particularly high contact pressurealong a narrow line between the sealing member 28 and the outer surfaceportion 70 of the free end 30 of the annular element 41.

For obtaining an effective sealing, it is further advantageous that theouter projection 50 is wedged and thereby deformed between outer andinner ridges 59, 60 of the annular element 41.

As is shown in FIG. 5B, the inner projection 51 is bent open as thesealing member 8 is deformed, so that pulling away of sealing membermaterial towards the bottom 56 of the annular member 55 and associatedcontact pressure relief is counteracted.

In particular in connection with the final mutual displacement of theannular element 41 and the sealing member 28, a particular issue is thatmost annular elements have one or more bridges 61 (FIG. 6) between outerand inner ridges 59, 60 of the annular element 41. Such bridges 61constitute an interruption of an annular head space 62 into which theouter projection 50 is wedged during the third stage. Leakage inparticular at the transitions where, in circumferential sense, thebridge begins and ends is diminished since the outer projection isshaped to roll and buckle radially outwards, so that excess sealingmember material is locally displaced away from the seal between theouter projection 50 and the annular element 41, thereby reducinginterference with this seal and allowing a substantially continuous sealalong a line passing underneath the bridge 61.

In the foregoing specification, the invention has been described withreference to specific examples of embodiments of the invention. It will,however, be evident that various modifications and changes may be madetherein without departing from the broader spirit and scope of theinvention as set forth in the appended claims.

1-81. (canceled)
 82. System for preparing a potable beverage from a capsule using a fluid supplied under pressure into the capsule comprising: a beverage preparation device comprising an enclosing member for receiving the capsule, wherein the enclosing member comprises fluid injection means for supplying fluid under pressure into the capsule, wherein the beverage preparation device further comprises a closing member, such as an extraction plate, for closing the enclosing member of the beverage preparation device, wherein the enclosing member of the beverage preparation device further comprises an annular element having a central annular element axis and a free contact end, said free contact end of the annular element optionally being provided with a plurality of radially extending open grooves; and a capsule containing a substance for the preparation of a potable beverage by extracting and/or dissolving the substance by means of supplying a fluid under pressure into the capsule, wherein the capsule comprises an aluminum capsule body having a central capsule body axis, said aluminum capsule body being provided with a bottom, a side wall and an outwardly extending flange, the capsule further comprising an aluminum cover attached to the outwardly extending flange, the cover hermetically closing the capsule, wherein the capsule further comprises a sealing member at the outwardly extending flange for providing a fluid sealing contact with the enclosing member of the beverage preparation device if the capsule is positioned in the enclosing member of the beverage preparation device and the enclosing member is closed by means of the closing member of the beverage preparation device, such that the outwardly extending flange of the capsule and at least a portion of the sealing member of the capsule are sealingly engaged between the enclosing member and the closing member of the beverage preparation device, characterized in that, the sealing member is integral with the outwardly extending flange and comprises at least one projection projecting from the outwardly extending flange, said at least one projection comprising a projection top, and wherein the at least one projection is configured such that its projection top exerts a radial force on the free contact end of the annular element if the capsule is positioned in the enclosing member of the beverage preparation device and the enclosing member is closed by means of the closing member of the beverage preparation device, wherein the sealing member comprises a further projection projecting from the outwardly extending flange and a plateau between said two projections, wherein the distance between the two projections is such that the free contact end of the annular element is positioned between the two projections if the capsule is positioned in the enclosing member and as the enclosing member is closed by means of the closing member, wherein the sealing structure and the remainder of the capsule body are made of the same plate material, and wherein the enclosing member and the projections are arranged such that, when the enclosing member and/or the closing member is moved towards the other with the sealing member in-between, the free contact end of the annular element may first contact the first one of the two projections and subsequently contacts the second one of the two projections.
 83. System according to claim 82, wherein a first one of the two projections projects further from a base portion of the outwardly extending flange, to which base portion the cover is attached, than a second one of the two projections.
 84. System according to claim 83, wherein the first one of the two projections is a radially inner one of the two projections.
 85. System according to claim 82, wherein the sealing member comprises an annular trough between an inner one of the projections and the side wall, the annular trough having a bottom axially spaced from the base portion to which base portion the cover is attached.
 86. System according to claim 82, wherein the plateau is axially spaced from the cover.
 87. System according to claim 85, wherein the bottom of the annular through is at a first axial distance from the cover and the plateau is at a second axial distance from the cover, said second axial distance being larger than said first axial distance.
 88. System according to claim 87, wherein the sealing member is deformable such that, in use, closure of the enclosing member deforms the side wall to cause the bottom of the annular trough to be brought substantially in contact with the cover.
 89. System according to claim 87, wherein the inner one of said two projections is shaped such that it is bent open if the sealing member is deformed such that the plateau contacts the cover.
 90. System according to claim 82, wherein a radially outer one of said two projections has a greater stiffness against radial outward deformation than the inner one of said two projections.
 91. System according to claim 82, wherein a first one of the two projections has an extreme top end extending around the capsule axis at a diameter of 29.2 to 29.8 mm and wherein a second one of the two projections has an extreme top end extending around the capsule axis at a diameter of 31.9 to 32.4 mm.
 92. System according to claim 82, wherein an outer one of said two projections has a generally inwardly facing surface portion extending at an enclosed angle of less than 8° and preferably less than 6° or less than 4° to the capsule body axis.
 93. System according to claim 82, wherein the distance between the two projections is such that the free contact end of the annular element is contacted by the two projections if the capsule is positioned in the enclosing member and the enclosing member is closed by means of the closing member.
 94. System according to claim 82, wherein the two spaced projections and the plateau are arranged such that the free contact end of the annular element is contacted by the plateau if the capsule is positioned in the enclosing member and the enclosing member is closed by means of the closing member.
 95. System according to claim 82, wherein the capsule comprises a bearing for the enclosing member if the capsule is positioned in the enclosing member and the enclosing member is closed by means of the closing member, said bearing enclosing at least a portion of the free contact end of the annular element and said bearing being formed by the two projections and the plateau there between.
 96. System according to claim 82, wherein, seen in cross-section along a plane through the capsule body axis, the plateau has a sloping section forming a transition to the outer one of said two projection, wherein the sloping section constitutes a relatively straight section between more curved sections.
 97. System according to claim 96, wherein the sloping section is oriented at an enclosed angle of at least 10° and more preferably at least 20° and at most and 60° and more preferably at most 50° relative to the cover.
 98. System according to claim 82, wherein the plateau is substantially flat.
 99. System according to claim 82, wherein the plateau comprises a curved portion, the plateau preferably being V-shaped.
 100. System according to claim 82, wherein an outer one of said two projections is shaped to roll and buckle radially outwards if compressed in axial direction, while in contact with an outwardly facing surface of a free end of the annular element positioned between the two projections.
 101. System according to claim 82, wherein a transition from the outer one of said two projections to a radially outwardly projecting flange of the a base portion to which the cover is attached has an internal radius of less than 0.15 mm and preferably less than 0.12 mm, a radially outer wall of said outer one of said two projections being oriented at an enclosed angle relative to the capsule body axis of less than 8° and more preferably less than 6°.
 102. System according to claim 82, wherein the at least one projection comprises a projection side wall which is inclined with regard to the outwardly extending flange of the aluminum capsule body, said projection side wall being configured such that it is deformed easily if the capsule is positioned in the enclosing member of the beverage preparation device and the enclosing member is closed by means of the closing member of the beverage preparation device.
 103. System according to claim 82, wherein said free contact end of the annular element has a first circumferential surface portion contacting said first projection, if the capsule is positioned in the enclosing member and as the enclosing member is closed by means of the closing member, and a second circumferential surface portion contacting said second projection, if the capsule is positioned in the enclosing member and as the enclosing member is closed by means of the closing member, wherein said radially extending open grooves are deeper in said first surface portion than in said second surface portion or said radially extending open grooves are absent in said second surface portion.
 104. System according to claim 96, and wherein the annular element is arranged for deformation of the sloping section.
 105. System according to claim 82, wherein the annular element has outer and inner ridges and wherein the outer one of said two projections is arranged to be deformed between said outer and inner ridges if the sealing member is clamped between the enclosing member and the closing member. 